Introduction of Islam

In 1380, Karim ul' Makhdum, the first Islamic missionary to reach the Sulu Archipelago and Jolo, brought Islam to what is now the Philippines.

The Sheik Karimal Makdum Mosque was the first mosque established in the Philippines on Simunul. Subsequent visits by Arab Muslim missionaries from the now culturized Malaysia and Indonesia, helped strengthen the Islamic faith in the Philippines, mostly in the south but as far north as Manila. Vast sultanates were established, comprising the Sultanate of Maguindanao and the Sultanate of Sulu. Since the first people who established themselves as sultans in various parts of the Malay Archipelago—Malaysia, Indonesia, and the Philippines—were usually of Arab descent, most people of royal lineage claim Arab descent, some going as far as claiming descent from the Prophet Muhammad himself.

Further immigration by Muslims to the Philippines by traders and proselytizers from Malaysia, Indonesia, India and the Arabia strengthened the foothold of the Islamic faith.^[16] By the 13th century, Islam was firmly entrenched in the Sulu Archipelago and spread from there to Mindanao; it had reached the Manila area by 1565.^[1] Although Islam spread to Luzon, Animism, syncretized with Hinduism and Vajrayana Buddhism, was still the religion of the majority of the Philippine islands.

Muslim immigrants introduced another political concept for territorial states by introducing Sultans exercising authority via a panglima, as opposed to the older Indianized Rajah system used at the time of the Laguna Copperplate Inscription. States that use this system include those of Sulu, Maguindanao and Seludong (Manila). When the Spaniards arrived in the 16th century, the majority of the estimated 500,000 people in the islands lived in barangay settlements some still ruled by Rajahs while others were already ruled by Sultans.^[1] There are also Rajahs that converted into Islam.

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